Relaxation processes in Au–TiB 2/GaAs structures under short-term thermal annealing

Abstract

The investigations of the structure parameters of Au–TiB 2/GaAs and TiB 2/GaAs device structures and their transformations at short-term thermal annealing were carried out. The metal films were magnetron sputtered on Czochralski-grown (001) GaAs in an argon atmosphere. The growth rate was ∼5 nm/s and the film thickness ranged from 10 to 50 nm. The samples were annealed for 1 min at 400°C, 600°C and 800°C. Using X-ray diffraction, scanning electron microscope (SEM) and scanning probe microscope (SPM) methods, it was shown that sputtering titanium diboride films causes the titanium and boron solid solutions to form as well as the appearance of some other phases in the interface region. Short-term annealing at above temperatures leads to elastic strain relaxation, changes of film morphology, decay of solid solutions and generation of dislocations. The relaxation processes differ for various types of structures.